How to build better, safer nuclear reactors.

Nuclear power plants will never be completely safe but they can be made far safer than they are today. The next generation of plants must be built to work with nature - and human nature - rather than against them. They must be safe by design, so that even if every possible thing goes wrong, the outcome will stop short of disaster. In the language of the nuclear industry, they must be "walkaway safe", meaning that even if all power is lost and the coolant leaks and the operators flee the scene, there will be no meltdown of the core, no fire in the spent fuel rods, and no bursts of radioactive steam into the atmosphere. For inspiration, consider the manhole. Manholes are round, because no matter how you rotate a round cover, it can never fall through a round hole. The solution is brilliant in its simplicity. The beginnings of manhole wisdom are incorporated into new nuclear ...